1. Field of the Invention
The present invention relates to recording medium conveying devices and image forming apparatuses including recording medium conveying device.
2. Description of the Related Art
Image forming apparatuses include copying machines, printers, facsimiles (each of which forms an image onto a sheet of paper by an electrophotographic method), or multifunction apparatuses. A sheet of paper is an example of a recording medium. In an image forming apparatus, a first conveying member feeds recording media (sheets) from a recording medium storage section to registration rollers. The recording medium storage section is located in the interior of a main body, and stores the recording media. A second conveying member feeds recording media from a bypass tray to the registration rollers.
Accordingly, the sheets held in the recording medium storage section, such as a sheet-feed cassette in the main body, are conveyed one at a time to the registration rollers by a conveying roller. The sheets loaded in the bypass tray are also conveyed to the registration rollers by a different conveying roller. The sheets fed from the sheet storage section in the main body or the sheets fed from the bypass tray are conveyed by the registration rollers to a transfer nip portion, of an image forming section, at a suitable time to form an image at the image forming section. Then, a toner image formed on an image bearing member, such as a photosensitive drum, is transferred onto each of the sheets that is conveyed to the transfer nip portion.
In the image forming apparatus, the registration rollers, the conveying roller of the first conveying member, and the conveying roller of the conveying unit are independently driven by respective motors.
A transfer conveying unit including at least the registration rollers and transferring member is formed so as to be removably mounted to the main body. When a sheet jams in the transfer conveying unit, the following structure is used to remove the sheet. To remove the jammed sheet in the transfer conveying unit, a knob connected to the conveying roller or a pressing roller of a fixing device is manually turned, rotating the conveying roller or the pressing roller of the fixing device. By rotating the conveying roller or the pressing roller of the fixing device, the jammed sheet is removed from the interior of the image forming apparatus.
However, in image forming apparatuses, of the type wherein the registration rollers, the conveying roller of the first conveying member, and the conveying roller of the second conveying unit are independently driven by respective motors, the number of motors is increased, thereby making the structure of the image forming apparatus complicated, and increasing costs.